This fixes warnings that are emitted when building with the `-analyze`
flag enabled.

IFileDialog::Show and CoUninitialize both seem to require the main
message loop to be active and running when they are called. If we block
the message thread while calling these functions, we may cause a
deadlock.

The destructor of the Win32NativeFileChooser was blocking the message
thread until the background thread exited, but the background thread was
unable to make progress while the message thread was blocked.

To work around this issue, we now pump the message thread in the
destructor of the Win32NativeFileChooser. If a dialog is currently
active, this should allow it to exit gracefully.

Note that we cannot use MessageManager::runDispatchLoopUntil here:
- MessageManager::runDispatchLoopUntil will not process any messages if
  the quit message has been received, which could lead to deadlocks if the
  FileChooser is destroyed after the quit message has been posted.
- This function isn't defined when JUCE_MODAL_LOOPS_PERMITTED is disabled.

MIDI: Several ALSA Seq improvements
===================================

Many things were done in this patch (I couldn't really split in several
patches):
 * Only one ALSA Sequencer client per application
 * ALSA Sequencer client name is the application's name by default
 * Fixed a bug when getDeivces() would return devices created by the
   application itself
 * Only ports created with createNewDevice() are allowed to be subscribed,
   other ports (created by openDevice()) doesn't allow subscription
 * AlsaPort is now handled by AlsaClient, basically having the proper
 representation such as the ALSA Sequencer has.

Files: Fix default directory paths
==================================

Some information on:
* Linux LSB FHS:
  http://www.linuxfoundation.org/collaborate/workgroups/lsb/fhs-30
* https://wiki.archlinux.org/index.php/Xdg_user_directories

Refactor Event loop to remove X11 dependency
============================================

The goal of this refactor was to remove X11 dependencies on juce_events
to enable non-gui applications (example, Embedded Linux apps) to have no
libx11 dependency.

The side-effect of this refactor is easy implementation of other Linux
graphical back-end, cleanup some code, better handling of X displays and
other benefits.

I removed a lot of the code from juce_linux_Windowing to separate files
for clarity. I also renamed all Linux X11 files to *linux_X11* instead of
just *linux*.

X11: Remove unnecessary XGrabButton call
========================================

This call is made unnecessary if used proper window flags when a window
is created.